Perhaps you should try some spelling variations:
trinh toan » tinh toan, thanh toan, trinh han
trinh van » trinh han, trinh quan, dinh van
su triet » su viet, su tien, ve triet
tu quynh » thu quynh, thuy quynh, truc quynh
tu sach » thu sach, su sach, te sach
sach tu » sach thu, cach tu, sach ty
hieu ve » hieu va, hieu van
tu nang » tru nang, tu nong, tu nano
tu quy » tu duy
ve nam » he nam, va nam, le nam
x hoi » xa hoi, o hoi, x ho

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach tu nang x hoi. hieu ve nam ((tu quy) or (tu quynh)) ((trinh van) OR (trinh toan)) su triet~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach tu nang x hoi. hieu ve nam ((tu quy) OR (tu quynh)) ((trinh van) OR (trinh toan)) su triet.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach tu nang x hoi. hieu ve nam ((tu quy) or (tu quynh)) ((trinh van) OR (trinh toan)) su triet".
• Adding a wildcard symbol may retrieve word variants: tu sach tu nang x hoi. hieu ve nam ((tu quy) or (tu quynh)) ((trinh van) OR (trinh toan)) su triet*.